The present invention relates to a centrifugal actuator assembly and more particularly to a centrifugal actuator assembly for actuating a starting switch for energization and deenergization of the starting winding of an electric motor, including an improved arrangement for positively positioning the actuator assembly for moveable operation relative first and second preselected positions and for limiting movement beyond such first and second positions.
It is well known in the electric motor art to actuate a switch for selective energization of stator windings used to generate required suitable forces for rotating the rotor assembly associated with the stator for both "start" and "run" conditions. The switch to be actuated conventionally is operated by a centrifugal actuator assembly mounted on and rotatable with the rotor shaft of an electric motor, the inwardly-outwardly moving levers of the centrifugal actuator assembly being responsive to the speed of the rotor shaft upon which the centrifugal actuator is mounted. Many of these centrifugal actuator assemblies of the prior art have included spring biased, weighted levers with the weights being capable of moving outwardly by centrifugal force acting against the spring biasing to effect axial shifting movement of a portion of the centrifugal actuator from a first position to a second position with respect to the rotor shaft. This movement is linked to a switch leading to motor windings effecting "start" and "run" conditions of the motor. In U.S. Pat. No. 4,661,732, issued on Apr. 28, 1987 to Louis M. Gehrt, it was broadly recognized to provide limiting structure to interrupt and prevent further outward movement of the spring biased switch actuating levers of a centrifugal actuator assembly in the event of improper actuating operations, the interrupting arrangement provided including lever camming surfaces cooperatively positioned with respect to a stop ledge to engage the levers in further outward movement to ensure alignment and snug nesting of the levers with the stop ledge in the event of improper actuating operation of the centrifugal actuator assembly.
The present invention, recognizing the advantages of such a safety stop ledge and camming surface arrangement in centrifugal actuator assemblies, further recognizes that such past arrangements have served to accommodate and limit improper actuator operations at only one actuator position. In addition, the present invention further recognizes that past centrifugal actuator arrangements have often resulted in operating problems, and have been involved in maintaining consistent engagement between a switch plunger and the centrifugal actuator associated therewith. Recognizing these past problems, the present invention provides an improved limiting arrangement which not only ensures alignment and snug nesting of the centrifugal actuator levers at both position of the moving levers but also ensures a positive and proper location of the actuating levers to maintain a consistent preselected engagement between actuator and associated switch plunger.
The present invention not only recognizes these past problems in the art, but resolves the same with an efficient straightforward and economical apparatus which can be readily manufactured with a minimum of parts and assembled without sacrifice of a number of known structural features of past centrifugal actuators.
Various other features of the present invention will become obvious to one skilled in the art upon reading the disclosure set forth herein.